Expansible wheel



Aug- 28, 1934. J. LEvoY Er As. 12,971,653

EXPANSIBLE WHEEL Filed 001'.. 14, 1935 4' 1NVENT0R5 JQLSEPH E Voy v BYHPMINH GREEN NEYS.

Patented Aug.. 28, 1934 UNITED NSTATES PATENT oFFicE @an Francisco, Calif.

Applicants center 14, ieee, serai No. 69eme il illaims.

The present invention relates to improvements in expansible wheels and more particularly has reference to polishing or bufng wheels in which an lendless band of sand paper or the like is used on a periphery of an expansible wheel for polishing purposes.

More particularly the present invention is an improvement over the invention described in the copending application of Joseph Levoy, one oi the applicants in this application, Serial No. 592,608, filed February l2, 1932, on an expansible wheel.

The principal object of the invention is to provide an expansible wheel of the character dew scribed that is self-contained, easy to manipulate,

economic in structure, and in which the endlessband is firmly held to its seat and is supported so asI to render its entire surface active at all times.

A further object of the invention is to provide an expansible wheel of the character described in which all the parts are firmly held against the effects of centrifugal force, and in which all possibility of parts loosening themselves is elimi.

purpose of expanding the rubber ring to a desired size.

Further objects and advantages of the present invention will appear as the specification proceeds.

The preferred forms of our expansible wheel are showirin the accompanying drawing, in which y Figure 1 shows a fragmentary sectional view t@ through a rubber ring used in connection with our invention;

Figure 2 a similar view of our expansion wheel in which compression rings are applied to the rubber ring in an intermediate` stage of compression;

Figure 3 a similar view showing the expansi-l lble 'Wheel in nal operative form;

Figure 4 a sideview of our expansible wheel complete; and

Figure 5 a fragmentary section through a modied form of expansible wheel.

While we have shown only the preferred forms of our invention we wish to have it understood that various changes or modifications may be made within the scope ofthe claims hereto 'at- (Gil. 51.-190) tached without departing from the spirit of the invention.

In our preferred forni we use as an essential element of our expansible wheel a ring 1 made preferably of rubber or similar elastic and ilexible material, the ring being shown as having a nat perpheralsurface 2, comparatively short side faces 3 and tapered under faces 4,. which terminate in an inner band 5 projecting toward the center of the ring and being much .thinner than the ring near its outer circumference. The band 5 has two anges `6 projecting laterally therefrom, the upper faces 7 of the anges being substantially flat while the lower faces 6 are tapered in 'the manner shown in the drawing. The band 5 projects inwardly beyond the nanges and is formed with tapered edges 9, the taper of these edges corresponding substantially to the taper of the under faces 4 and being preferably slightly steeper.

1t will be understood that the outer face 2 of the wheel may be made flat as shown in the drawing, or may be made of any other desired' configuration, concave or convex, or slightly il-shaped, depending upon the use to which the expansible wheel is to be put.

In combination with this rubber ring we provide two compression rings l0 having tapered edges 11 adapted for engagement, from opposite sides-with the tapered under edges of the rubber ring. Below or inside of the tapered edge 11 each compression ring has a short straight portion 12, corresponding substantially in length to the straight 'portion of the band 5 between the under edges and the anges and inside of this straight portion each compression ring is formed with an annular recess 13 adapted to receive the corresponding flange 6 of the rubber ring. 1t will be noted, however, that while the upper face 7 of each flange 6 is substantially straight, theA upper edge 14 of the recess'is tapered, while its lower face 15 is substantially straight. inside of the recess each compression wheel is formed with a tapered edge 16 which in nal position substantially corresponds and registers with the tapered edge 9 ofthe rubber ring.

In this manner when vthe two compression rings are engaged with opposite sides of the rubberv ring, and are urged together, the tapered faces 11 of the compression rings engage the under edges 4 of the rubber ring, while the flanges 6 are accommodated in the recesses 13 and upon initial compression4 are bent inwardly by the slanting faces 14 of the ltvvo recesses in the manner shown in Figure 2.` During the movement of l the compression rings toward each other the' outer edges of the rubber ring will have a tendency to be forced out more rapidly than the central portion with the result that the outer surface of the rubber ring will be concave. In order to overcome this, we have provided the slanting edges' 16 of the compression rings which will engage with the slanting edges 9 of the rubber ring and tend to crowd the middle portion of the band outward, this outward movement of, the inner portion of the band being somewhat quicker than the outward movement of the edge portions of the rubber ring because of the steeper taper of the edges 16 than the'edges 11, whereby the rim of the rubber ring will be straight. When finally tightened as shown in Figure 3, the compression rings fully engage with the rubber ring, the flanges 6 of the rubber ring assume substantially the shape defined bythe recesses of the expansion element, and the entire band is crowded together to some extent by the slant-A ing edges 16 of the compression element, whereby the rubber ring is rmly anchored against outward movement by the compression rings, while on the other hand the outer peripheryof the rubber ring is expanded against a ring of abrasive material 17 which has been previously applied to the rubber ring. The same `movement which causes the sides 16 to engage with the inclined sides 9 of the rubber ring and force the 'central portion of the ring outwardly is tilized in causing the sides 14 to engage with the sides .7 and to force the fianges' inwardly for anchoring the rubber ring to the compression rings so 35 l,that the rubber ring is held against expansion due to centrifugal force.

v For assembling and initially compressing the two compression rings, we preferably use a series of bolts 18, each bolt being slidable in one of .the compression rings as at 19, and threaded into the other compression ring as at 20, while the head 2J,A of the bolt is free to move in a recess 22, and bears upon a shoulder 23 formed by the recess. A 'spring 24 yopposes compressive ,movement It will be seen that when the bolt Jis screwed home the two compression rings are tightened upon the rubber ring to a certain extent, but that lthe final compressive movement islcaused by another agency to.be described later, the bolts being arranged in such a manner as not Jto interfere with further compressive movement. i The bolts are preferablyarranged in diametrically opposing pairs -and in such order that the bolts of one pair are threaded into one of the compression rings, while the bolts of the 'otherl pair are threaded into the other compressionlring. l'

- For final compression of the compression rings and expansion of the rubber ring the wheel as- .sembled as shown in AFigure ``2Yis placed upon the end ofthe shaft 26, and is tightened upon the shoulder 27 of tlie shaft by means of a nut 28. The abrasive band 17 is placed over the rubber ring before nal tightening, and is di- .mensioned to make' a snug fit upon tightening.

The form shown in Figure 5 differs slightly.

l( The manner in which our expansible wheel is ll,971,653 l to be used will be readily understood from the foregoing description. The two compression ringo are engaged with opposite faces of the rubber ring with the springs 24 in place and the bolts 18 are then applied in the manner previously de.- scribed, and screwed home to ex the flanges 6 inwardly in the recesses 13 and to partly expand the rubber ring. After the wheel is thus assembled it is placed upon the shaft 26 so as to rest against the shoulder 2'7 and the final tightening is brought abo'ut by means of the nut 28. 'I'he tightening of the two compression rings upon the rubber ring causes the latter to expand, while at the same time the flanges 6 are anchored in the recesses 13 and the rubber material of the band 5is further compressed by means of the tapered edges 16. The band with its flanges is therefore firmly anchored in the recesses of the compression rings and there is no danger Whatever ofthe rubberV ring working loose during operation.

We claim:

1. An expansible wheel comprising a rubber ring having tapered under edges, compression rings having tapered edges engageable with the under edges on opposite sides of the rubber ring, means for tightening the compression rings upon the rubber ring whereby the latter is expanded and means for interlocking the rubber ring and the compression rings, the said means comprising flanges making a sharp angle with and projecting from the rubber ring interiorly of the under edges and recesses in the compression rings adapted to receive the flanges;

2. An expansible wheel comprising a rubber ring having tapered-under edges, a band projecting inwardly therefrom and iianges projecting laterally from the band, compression rings having tapered edges engageable with the under edges on opposite'sides of the rubber ring, and means for tightening the compression rings upon the rubber ring whereby the latter is expanded, the compression rings having tapered recesses adapted to receive the flanges and to bend the Asaine inwardly when the compression ringsare tightened.

3. An expansible wheel comprising a rubber ring having tapered under edges, a band pro- `jecting inwardly therefrom and flanges pojecting laterally from the band, compression rings having tapered edges engageable with the under edges on opposite sides oi' the rubber ring, and means for tightening the compression rings upon the rubber ring whereby the latter is expanded, the compression rings having tapered recesses adapted to receive the flanges and to bend the sameinwardly when the compression rings are tightened, and the lband and the compression rings having tapered edges engaging one another for crowding the band material outwardly during the same operation. s

' 4. An expansible wheel comprising a rubber ring having tapered under edges, compression rings having tapered edges engageable with the under edges on opposite sides of the rubber ring, means for tightening the compression rings upon the rubber ring whereby the latter is expanded, the said means comprising bolts slidable in one of` the compression rings and threaded into the other compression ring with heads bearing on the first ring for bringing about a desired degree of compressive movement without interfering with further compressive movement and means independent of the bolts for compressing the rings together still further.

remets 5. hn expansible wheel comprising a rubber ring having tapered under edges, compression rings having tapered edges engageable with the under edges on opposite sides of the rubber ring, means for tightening the compression rings upon the rubber ring whereby the latter is expanded, the said means comprising bolts slidable in one of the compression rings and threaded into the other compression ring with heads bearing on the nrst ring for bringing about a desired degree of compressive movement without interfering with further compressive movement, and the boltheads being accommodated in recesses in the first compression ring so as to stay within the confines of the said ring even upon further compressive movement and means independent of the bolts for compressing the rings together still further.

6. An expansible wheel comprising a rubber ring having rtapered under edges, compression rings having tapered edges engageable with the under edges on opposite sides of the rubber ring and means for tightening the compression rings upon the rubber ring whereby the latter is expanded, the said means comprising bolts slidable in one of the compression rings and threaded into the other compression ring with heads bearing on the first ring for bringing about a desired degree of compressive movement without interfering with further compressive movement, and the bolts being arranged in pairs of oppositely disposed bolts threaded alternately into one and the other compression ring.

7. An expansible wheel comprising a rubben ring having tapered under edges with anges, the sides of vthe flanges disposed adjacent to the tapered under edges extending at right angles to the center plane of the ring and constituting nontapered sides, compression rings having tapered edges engageable with the tapered under edges on opposite sides of the rubber ring, said compression rings having annular recesses with tapered walls for engaging with the non-tapered sides of the flanges, and means for tightening the compression rings upon the anges for bending the iianges inwardly for securing the rubber ring in place.

\ 8. An expansible wheel comprising a rubber ring having annular flanges with their outer peripheral sides extending at right angles to the center-plane of the ring, compression rings disposed on opposite sides of the rubber ring and having annular recesses forA receiving the flanges, the outer peripheral sides of the recesses being inclined for bending the flanges inwardly when the rings clamp thelrubber ring, whereby the rubber ring is securely anchored to the compression rings, and means for securing the compression rings together.

9. An expansible wheel comprising a rubber ring having tapered under edges, a central web, and flanges extending from the web, said web projecting inwardly beyond the flanges and having tapered under edges, and compression rings having tapered edges for engaging with the rst and second named tapered under edges of the rubber ring for expanding it so that the outer periphery of the ring will be straight, said compression rings also having recesses with tapered sides for forcing the iianges inwardly for anchoring the rubber ring to the compression rings and for preventing the stretching of the rubber ring due to centrifugal force.

' JOSEPH'LEVOY.

ARMIN H. GREEN.

MNB 

